Polarization Control in Integrated Graphene-Silicon Quantum Photonics Waveguides

Area of Science:

• Photonics
• Materials Science
• Nanotechnology

Background:

• Silicon photonics is crucial for integrated circuits.
• Controlling light polarization is essential for optical communication and sensing.
• Graphene's unique electronic properties offer potential for novel photonic devices.

Purpose of the Study:

• To numerically investigate graphene nanoribbons for polarization control in silicon-on-insulator (SOI) strip waveguides.
• To identify key factors influencing polarization control performance.
• To explore methods for optimizing device performance, including insertion loss and polarization extinction ratio.

Main Methods:

• Numerical simulations were performed to analyze the interaction of light with graphene nanoribbons on SOI waveguides.
• The study focused on varying graphene chemical potential and waveguide geometrical parameters (widths, distance).
• The impact of oxide spacer thickness on device performance was also investigated.

Main Results:

• Graphene chemical potential and waveguide geometry significantly affect polarization control.
• Waveguide width tapering was shown to enable both TE-pass and TM-pass polarizing functionalities.
• Increasing the oxide spacer thickness reduced insertion losses while maintaining a high polarization extinction ratio.

Conclusions:

• Graphene nanoribbons are a viable solution for polarization control in silicon photonic integrated waveguides.
• Tunable polarization control can be achieved by manipulating graphene chemical potential and waveguide dimensions.
• Optimizing the oxide spacer thickness is key to balancing insertion loss and polarization performance.